1. Field of the Invention
Embodiments of the present invention generally relate to data backup and restoration techniques and, more particularly, to a method and apparatus for efficiently identifying and restoring data blocks which require to be restored in a recovery system.
2. Description of the Related Art
Currently, data is backed up to and restored from computer storage in order to provide protection from data loss if the original data becomes corrupted or damaged due to various reasons, such as a component failure (like hardware or software failure), a natural disaster, or other technical disaster (such as virus attacks). The recovery of such data involves number of operations for restoring the data blocks to a volume.
In addition, some conventional techniques, such as snapshot-based backup techniques, take a snapshot and then, back up the data blocks. The snapshot is created at a predetermined point-in-time. Snapshots are generally created on some regular schedule. The snapshot is stored on-disk along with the active file system, and is called into the buffer cache of the filer memory as requested by the storage operating system. These techniques, generally, are more complex to implement and take more time for data restoration.
Furthermore, the recovery process restores data blocks that are already in the volume. The conventional techniques are not that efficient as the data blocks which are not changed from a recovery point are also restored. Hence, the conventional techniques restore duplicate and unchanged data blocks to the volume and hence, these conventional techniques are inadequate for allowing speedy restoration of the data.
Therefore, there is a need in the art for a method and apparatus for efficiently identifying data blocks required for restoration.